Update Changelog with 1.9.0 release (#4904)

Signed-off-by: Agustín Martínez Fayó <amartinezfayo@gmail.com>

CHANGELOG.md

@@ -1,5 +1,41 @@
 # Changelog
 
+## [1.9.0] - 2024-02-22
+
+### Added
+
+- `uniqueid` CredentialComposer plugin that adds the x509UniqueIdentifier attribute to workload X509-SVIDs (#4862)
+- Agent's Admin API has now a default location defined (#4856)
+- Partial selectors from workload attestation are now logged when attestation is interrupted (#4846)
+- X509-SVIDs minted by SPIRE can now include wildcards in the DNS names (#4814)
+
+### Changed
+
+- CA journal data is now stored in the datastore, removing the on-disk dependency of the server (#4690)
+- `aws_kms`, `azure_key_vault`, and `gcp_kms` KeyManager plugins no longer require storing metadata files on disk (#4700)
+- Bundle endpoint refresh hint now defaults to 5 minutes (#4847, #4888)
+- Graceful shutdown is now blocked while built-in plugin RPCs drain (#4820)
+- Entry cache hydration is now done with paginated requests to the datastore (#4721, #4826)
+- Agents renew SVIDs through re-attestation by default when using a supporting Node Attestor (#4791)
+- The SPIRE Agent LRU SVID cache is no longer experimental and is enabled by default (#4773)
+- Small documentation improvements (#4764, #4787)
+- Read-replicas are no longer used when hydrating the experimental events-based entry cache (#4868)
+- Workload gRPC connections are now terminated when the peertracker liveness check fails instead of just failing the RPC calls (#4611)
+
+### Fixed
+
+- Missing creation of events in the experimental events-based cache entry when an entry was pruned (#4860)
+- Bug in SPIRE Agent LRU SVID cache that caused health checks to fail (#4852)
+- Refreshing of selectors of attested agents when using the experimental events-based entry cache (#4803)
+
+### Deprecated
+
+- `k8s_sat` NodeAttestor plugin (#4841)
+
+### Removed
+
+- X509-SVIDs issued by the server no longer have the x509UniqueIdentifier attribute as part of the subject (#4862)
+
 ## [1.8.7] - 2023-12-21
 
 ### Added